Roll holder for rivet spinning machines



Aug. 9, 1938. H. L. TuRNQuisT Erm., 2,126,427

' f ROLL HOLDER FOR RIYET SPNNING MACHINES Filed Jan. 27, 1937 l l l I l l l I BY a. ng.

A TTORNE Y Patented Aug. 9, 1938 UNITED STATES PATENT OFFICE VROLL HOLDER FOR RIVET SPINNING MACHINES Application January 27, 1937, serial No. 122,507

1 Claim.

This invention refers to roll-holders such as are commonly used for rivet spinning machines and as such is adapted to be used on various types of spinning machines. Y

The majority of rivet spinning machines employ holders carrying a pair of rolls mounted side by side in a manner to turn on a horizontal axis and as the roll-holders are largely employed for forming oval or mushroom type of heads, they necessarily employ .a pair of rolls which are mounted in close proximity to each other and have their inner adjacent peripheral edges cut out more or less so that the two rolls working upon the rivet will form a rounded head. The operative contact of the bevel faced rolls upon an oval rivet head, through the medium of a rivet spinning machine, necessarily tends to spread the rolls as' against the cheeks ofthe holder, and thereby imparts lateral strain upon the screw or pin upon which the `rolls are mounted. This constant operative strain of the rolls and holder has a very strenuous effect upon the screw and cheeks of the holder and sooner or later causes them to wear, varying of course, in accordance with the structure of the screw and uses to which the holder is put.

The object,` therefore, of thisvinvention is to improve upon roll-holders of this class by providing a bearing upon which the rolls may freely rotate in their riveting operations, without becoming loosened through the operation of the holder and yet at the same time to provide a bearing, in the form of a screw, which may be tightly secured, to stand the strain and wear imposed upon it, yet at the same time to design the screw and the parts of the holder in which it is mounted, so as to permit the screw to be freely inserted, adjusted, secured and removed as occasion may require.

This means as will later be seen, comprises a screw having a relatively long head having a delicately tapered periphery and a hexagonal or other form of shouldered socket in the end of the head central of its axis and of suilcient depth to receive a key for turning the screw.

In the accompanying drawing forming part of this specification similar characters of reference denote like or corresponding parts throughout the several figures and of which:

Fig. 1 shows a side elevation of one type of rivet spinning machine, manufactured by the assignee of this invention, and adapted to use a roll-holder or spinning head of my present invention.

Fig. 2 shows a vertical cross section, on an enlarged scale, of the roll-holder mounted in the machine illustrated in Fig. 1 and taken on line 2-2 of Fig. 3, together with a key with which the screw of the holder is operated.

Fig. 3 shows a side elevation, on an enlarged scale, of the roll holder shown in Figs. 1 and 2, and

Fig. 4 shows a further enlarged sectional elevation of the bearing screw and cheeks of the roll-holder, for the mounting of the rolls and illustrating the relation of the screw .and cheeks.

The type of roll-holders illustrated in the present application is of a design, manufactured by the assignee of this application and shows the rolls mounted in the holder at an angle to each other and upon a special shaped screw designed to support the rolls in a way to'insure their free operation. These rolls have their inner peripheral edges beveled, and thus have a great tendency to spread apart at the lower edges and cause wear on the holder and tensile strain upon the screw.

In the drawing IIJ indicates a pedestal of the machine shown in Fig. 1, II an adjustable table upon which the work is to be positioned, I2 a motor which serves to operate the rotary spindle I3 to which my improved roll-holder I4 is detachably connected.

This roll-holder is, for the most part, of a commercial type Aand comprises a body having a threaded socket I5 in its upper end surrounded by a hexagonal shouldered top portion I6 and depending from which is the cylindrical shaped body. This body is provided with an opening I'I through its central portion, the upper part of which is divided by a web I8 to separate the upper portion of the two rolls I9 and 2|] which are mounted upon a screw 2|. The screw is positioned in aligned openings 22 and 23 in the side cheeks 24 of the holder and extend through the holder at a right angle to the rolls which are rotatably mounted upon the intermediate smooth portion of the screw. The inner end portion of the screw is threaded as at 25 to engage the threaded opening 22 of the hole in one of the cheeks 24 of the holder. The aligned opening 23 in the other cheek of the holder serves as a bearing for the head of the screw and is tapered slightly as indicated in Figs. 2 and 4 which taper extends from the outer face to near the inner face of the cheek, thereby forming an elongated tapered bearing in a manner to produce greater friction against turning whereby the turning of the screw within the cheek is practically prohibited except when manually operated.

As will be seen from Fig. 4 the screw is proportioned with respect to the side members of the holder and the two rolls so that the hole 23 in the cheek of the holder is shaped and proportioned to correspond to the shape of the tapered head portion of the screw` so that the taper a of the head of the screw and the cheek of the holder meet the cylindrical bearing lportion b of the screw, as at c, and the corresponding cylindrical Y portion of the hole in the holder slightly inward of the inner face of the cheek so that in the tightening ofthe screw the tapered portion of the head will not extend through the inner face of the holder and thus engage the hole in the roll. This insures the closing together of the cheeks to take up wear of the rolls and -holder without plugging the hole of the roll and preventing them from turning. A somewhat similar effect is obtained on the threaded end of the screw as will be noted from this same Fig. 4

where the threads of the hole 22 are not cut clear through to the inner face of the roller but instead a narrow annular recess d is formed in the inner end of the hole to receive that end of the bearing portion of the 'screw not threaded, there being no portion of the thread thus exposed for the rolls to run on yet insures a grip of the thread with the cheek of the holder to bring about a gentle closing together of the two side members by the turning of the screw suilcient to take up any wear and yet allow the rolls to run free as is, of course, necessary to insure proper riveting operations.

The head portion of this screw is provided with a shouldered pocket 2l in line with the axis of the screw to receive a key 26 for operating the screw and whereby the same may be turned up tight enough to prevent it from'working loose during the operation of the head.

The use of a screw having a head with an elongated tapered side wall slightly short of the thickness of the cheek of the head is greatly enhanced when used in a similarly tapered socket of a roll-holder; Thesocket in the head for the reception of a key with which tooperate it also serves to advantagesince it would be diicult if not impossible 'tov operate a screw of this type in a holder'of this kind if it had an ordinary screw slotted head.

The rolls, as shown in the drawing, are mounted in diverging relation upon the intermediate portion of the screw within the opening forming the two spaced apart cheeks or side portions of the holder and have their upper portions separated by a n such as is now somewhat generally used in holders of this type so that the inner side faces of the rolls are in bearing contact with each other while their outer faces are in bearing contact with the side walls of the cheeks of the holder. This obviously provides practically no lateral play of the rolls so that the two operate as one upon the rivet head except that, of course, one turns in one direction and the other in the opposite direction, due to the rapid turning of the roll-holder and its spindle.

Having thus described our invention what we claim and desire to secure by Letters Patent is:

A roll-holder for rivet spinning machines, comprising a holder having spaced apart cheeks defining an opening having diverging opposite walls, said cheeks having aligned screw receiving passages therethrough, one of said passages being partially threaded and including an annular recess adjacent its inner end, the passage in the other cheek being conically tapered at an angle of twenty degrees, a screw positioned in said passage having a threaded end portion to engage the threadedl passage in the first mentioned cheek of the holder, and having a plain cylindrical bearing surface and a conical tapered head coextensive with the tapered portion of the passage in the other cheek, the said taper of the head of the screw and the taper of the passage in the cheek being such as to prevent the taper `of the screw from extending through the cheek and to insure a frictional engagement of one with respect to the other, a pair of rolls rotatably mounted in divergent relation on said bearing surface between the two cheeks, the said head also being provided with a central longitudinal shouldered socket to receive an operating key whereby the screw may be set in position.

HENRY L. TURNQUIST. FRANK A. HEILMAN. 

